My first beer is getting ready, I bottled 2-3 weeks ago. But why are
the differences in taste between the big (0,5l) and the small (0,33l)
bottles so damn big?

The beer in the small bottles is smooth, fresh, malty. The taste in
the big ones is raw, fruity, lot's of bubbles. Why is the beer in the
small ones so good? What can I do now and what can I do to prevent
this in the future?

Marcus Räder wrote:
How did you prime your beer?
Did you mix some kind of "sugar" with the whole batch or did you do it
by individual bottle?
Did you sanitize all the bottles the same?
If you sanitized the same, and primed the whole batch at once, the
bigger bottles should have, maybe, just a little less carbonation.

There's no magic in bottle size, the beer in both should taste the same.
A few
tips do come to mind, some of which have been mentioned before in this

thread:

1. Boil the sugar you are going to use for priming in a small amount of
water
and leave it to cool.

2. Pout the sugar solution to your bottling bucket, and siphon the beer
from
the fermenter to the bottling bucket leaving the sediment behind.

Usually this is enough to mix the sugar evenly in the beer, but if
you're
feeling
unsure, you can always mix it carefully with a long spoon or similar.

3. When you're cleaning old bottles for the first time, it's a good
idea to
check each bottle individually after cleaning. There can be some odd
stains
and stuff growing in recycled bottles, and some of the stains can be
really
hard to clean.

Once you get the bottles properly cleaned your life as a brewer will be
easy.
Just rinse the bottles after each use and sanitize before the next use.

Try leaving your beer for at least 6 weeks before drinking. When making your
first brew, it is always a temptation to give it a go, DONT. Let it age. My
best homebrew was a batch I had placed under the house and forgot about.
After six months, I found it and couldnt believe the quality.

We had the same experience...the big bottles might just take a little
longer because after us not drinking them( cause they tasted "raw") and
letting them sit longer, the actually started to taste better...or we
were fooling ourselves. Now we just use 22 oz bottles..the other ones
were close to quart size!